Seven years of COMPASS -- Inductively defined relations: A brief tutorial extended abstract -- On the role of category theory in the area of algebraic specifications -- Unification of theories: A challenge for computing science -- The larch shared language: Some open problems -- The lambda calculus as an abstract data type -- Unifying theories in different institutions -- Interchange format for inter-operability of tools and translation -- Experiments with partial evaluation domains for rewrite specifications -- Class-sort polymorphism in GLIDER -- Deontic concepts in the algebraic specification of dynamic systems: The permission case -- Reification — Changing viewpoint but preserving truth -- A category-based equational logic semantics to constraint programming -- Concurrent state transformations on abstract data types -- A view on implementing processes: Categories of circuits -- Combining algebraic and set-theoretic specifications -- Minimal term rewriting systems -- InterACT: An interactive theorem and completeness prover for algebraic specifications with conditional equations -- Rewriting and reasoning with set-relations II: The non-ground case completeness -- Termination of curryfied rewrite systems -- Formal specifications and test: Correctness and oracle -- Behavioural equivalence, bisimulation, and minimal realisation -- Using limits of parchments to systematically construct institutions of partial algebras -- Behavioural specifications in type theory -- Swinging data types -- Context institutions -- Object-oriented functional programming and type reconstruction -- Moving between logical systems -- Modular algebraic specifications and the orientation of equations into rewrite rules -- A model for I/O in equational languages with don't care non-determinism -- Tool design for structuring mechanisms for algebraic specification languages with initial semantics.

This book contains a strictly refereed selection of revised full papers chosen from the papers accepted for presentation during the 11th Workshop on Abstract Data Types held jointly with the 8th COMPASS Workshop in Oslo, Norway, in September 1995. The 25 research papers included were chosen from 57 pre-selected workshop presentations; also included are six invited contributions. The volume reports the progress achieved in the area of algebraic specification since the predecessor meeting held in May 1994.